Perfusion manifold assembly

A fluidic device comprising a substrate 10 having a first surface with one or more fluidic ports wherein the surface is adapted to stably retain one or more liquid droplets 23 of a first liquid at the one or more ports. The surface may comprise hydrophilic or hydrophobic regions, or geometric features such as a ridge, mount, gasket or depression to retain or confine the droplet to the port. A system comprising a fluid source in communication with a first fluid port positioned on a first mating surface wherein the first fluid port comprises a first protruding fluid droplet, a microfluidic device 16 comprising a channel in communication with a second fluid port on a second mating surface wherein the second fluid port comprises a second protruding droplet 22, and a mechanism for bring the two protruding droplets in a droplet to droplet connection such that fluid can flow from the fluid source through both ports into the microfluidic device. The drop-to-drop connection or coupling reduces the chance of bubbles becoming trapped during connection of ports of substrates. The system may form part of a perfusion manifold assembly.